This invention relates generally to tiltable material storing and dumping hopper assemblies which have both stand-alone or stationary ground mounting capability and the capability of being lifted and transported by means of either a fork lift truck or a farm or garden tractor which employs a standard vertically movable three-point hitch mechanism, Additionally, this invention relates to means for the self leveling of a hopper support: frame used in such assemblies when being lifted from and lowered to a ground mounted position by such a three-point hitch mechanism.
Generally speaking, material handling attachments, such as tiltable buckets and hoppers, which can be lifted and transported by means of a three-point hitch mechanism contained on a farm or garden tractor, have long been known and used in the prior art. See for example, the loader bucket assemblies operated by tractor three point hitch mechanisms as disclosed in U.S. Pat. No. 4,897,013 issued to R. H. Thompson et al. on Jan. 30, 1990); U.S. Pat. No. 4,915,013 issued to J. W. Langenfeld et al. on Apr. 10, 1990; and U.S. Pat. No. 2,624,481 issued to C. B. Richey on Jan. 6, 1953. also the frame supported bucket of Japanese pat. no. 58-71271 and tiltable hopper of West German pat. no. DE 3016-037, both of which are operated by a vertically movable tractor hitch.
The bucket assemblies disclosed in the previously identified U.S. patents are primarily adapted for digging and shoveling dirt and other bulk materials and for transferring the same to other locations and/or containers, rather than for use as hoppers for the more or less long term storage of materials. Moreover, none of these reference buckets are adapted for stand alone, stationary mounting and storage of materials, separate and apart from its three point hitch mechanism. Also, none of these assemblies is tiltably operable, separate and apart from its tractor hitch mechanism. Finally, none of these reference bucket assemblies is tiltably seated on a ground mountable frame bed.
As to the assembly disclosed in the Japanese patent, while it includes a bucket which is supported on a vertically movable fork lift frame and is capable of stand alone ground mounting on the frame under certain limited conditions, it is not tiltable relative to the frame to dump materials stored therein. The material storage hopper disclosed in the West German patent is of the stand alone, self supporting type, but is not tiltably supported on a frame of any kind. And while the subject hopper can be lifted, tilted and transported directly by a tractor three point hitch, it does not contain means for self leveling of the hopper when elevated to a given height above the ground by its three point hitch. Neither can the hopper of the West German patent be tilted to dump materials stored therein when in its stationary stand alone condition without the exercise of considerable manual effort, if at all. Lastly, none of the reference hopper assemblies include a ground mountable hopper support frame upon which a hopper is tiltably supported, which frame can be lifted either by a fork lift or by a three point hitch mechanism of a tractor, truck or other vehicle.
By means of my invention, these and other difficulties encountered using three point hitch liftable, tiltable hopper assemblies of the prior art are substantially overcome.